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991.
992.
Ten types of microscopically identifiable airborne fungal spores at Leiden,The Netherlands 总被引:3,自引:3,他引:0
A universal method for the complete assessment of atmospheric fungal spores does not exist, which is continuous, volumetric and non-selective, and offers at the same time reliable identification of the collected spores. To perform a survey of airborne fungal spores, a choice has to be made between a viable and non-viable method. For the study carried out in Leiden, the non-viable, continuous volumetric method has been employed, showing the results over a period of 10 years, for 10 microscopically identifiable fungal spore types. Of this selection,Cladosporium spores have by far the highest airborne quantities, with an average annual total of the daily averages of over 700 000.Botrytis, Ustilago andAlternaria follow with much lower spore concentrations of between 20 000 and 30 000 as annual totals. The spore types ofEpicoccum, Erysiphe, Entomophthora, Torula, Stemphylium, andPolythrincium are represented with annual sums lower than 10 000. A spore calendar shows the overall seasonal appearance of the 10 selected types. 相似文献
993.
Martina Bhm R. Lw Angela Haag-Kerwer U. Lüttge Th. Rausch 《Plant biology (Stuttgart, Germany)》1993,106(5):448-453
Understanding the taxonomiy of the tropical genus Clusia (Fam. Clusiaceae, Ord. Theales) has been hampered by the difficulties inherent in studying tropical dioecious, succulent, arborescent, epi- or hemiepiphytic taxa. Species identification by morphological traits often requires the terminal inflorescences and/or the succulent capsular fruits. To allow species differentiation based exclusively on vegetative tissue, a frequent necessity during ecological field studies, a procedure has been developed for rapid isolation of genomic DNA from Clusia leaf tissue followed by DNA amplification fingerprinting with a set of single arbitrary oligomer primers (23–27 mers). Fingerprints obtained with independent DNA preparations from one individual as well as DNA preparations from several individuals of the same species were identical for the major amplification products, although minor bands were somewhat variable. Polymorphic fingerprints have been obtained with 3 different primers for 3 Clusia species (C. minor L., C. alata Pl. & Tr., C. multiflora H. B. K.), and the related Oedematopus obovatus Spruce ex. PL (Clusiaceae). The interspecific Randomly Amplified Polymorphic Markers (RAPDs) thus obtained allow a rapid identification of vegetative tissue samples collected in the field, and will assist in a revision of the controversial taxonomy of the genus Clusia. 相似文献
994.
Maria Koufaki Theano Fotopoulou Efstathios K. Iliodromitis Sophia-Iris Bibli Anastasia Zoga Dimitrios Th. Kremastinos Ioanna Andreadou 《Bioorganic & medicinal chemistry》2012,20(19):5948-5956
Novel purine analogues bearing nitrate esters were designed and synthesized in an effort to develop compounds triggering endogenous cardioprotective mechanisms such as ischemic preconditioning (IPC) or postconditioning (PostC). The majority of the compounds reduced infarct size compared to the control group in anesthetized rabbits, whereas administration of the most active analogue 16 at a dose of 3.8 μmol/kg resulted on a significant reduction of infarct size, compared to PostC group (13.4 ± 1.9% vs 26.4 ± 2.3%). These findings introduce a novel class of promising pharmacological compounds that could be used as mimics or enhancers of PostC. 相似文献
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996.
A. Th. Czaja 《Planta》1936,26(1):90-119
Ohne Zusammenfassung 相似文献
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Summary A model for the simulation of leaching of non-adsorbed anions is described. The model can also be used to study the degree of salinization by evaporation.The accent is laid on usefulness under practical conditions. In view of this it has been assumed that transport of ions is only caused by mass flow and hydrodynamic dispersion.Data about soil and profile, initial water and salt conditions and ground-water level must be known. Given a precipitation and evaporation distribution the model can compute the leaching or accumulation of nitrate or chloride during a long period ofe.g. 125 days.The results of a number of computations are compared with theoretical expectations and actual measurements. There is a passably good agreement. 相似文献